The troubleshooting command displays information about the Cisco device's operations, generated or received traffic, and any error messages. The information is provided in real time until the user disables debugging or restarts the device.
The debugging operation consumes a lot of CPU resources and should not be used frequently in production environments. It is only a short time that is a debugging tool. You can choose to debug only certain events, such as: EIGRP information, received ICMP messages, etc.
Consider the following example:
R1 # debug ip icmp
ICMP packet debugging is enabled
R1 #
R1 #
ICMP: echo response sent, source 10.0.0.2, dst 10.0.0.1
ICMP: echo response sent, source 10.0.0.2, dst 10.0.0.1
In the above example, you can see that I only enabled debugging for ICMP events (such as pings). At the output you can see that R1 responded with two IP response packets to the unit with the IP address 10.0.0.1.
To disable ICMP event debugging, type the command with the no keyword:
R1 # no debug ip ipmp
ICMP packet debugging is disabled
To troubleshoot only RIP messages, run the following command:
R1 # debug ip rip
Troubleshooting the RIP protocol is enabled
R1 #
R1 # RIP: Update version 2 from 10.0.0.1 to GigabitEthernet0 / 0 received
172.16.0.0/16 over 0.0.0.0 in 2 jumps
192.168.5.0/24 over 0.0.0.0 in 1 jump
RIP: Version 2 update from 10.0.0.1 to GigabitEthernet0 / 0
172.16.0.0/16 over 0.0.0.0 in 16 jumps
192.168.5.0/24 over 0.0.0.0 in 16 jumps
You can enable debugging of all operations on your device by issuing the debug all command (do not use the command on production units, as it may result in significant output and crash the device!)
The debugging operation consumes a lot of CPU resources and should not be used frequently in production environments. It is only a short time that is a debugging tool. You can choose to debug only certain events, such as: EIGRP information, received ICMP messages, etc.
Consider the following example:
R1 # debug ip icmp
ICMP packet debugging is enabled
R1 #
R1 #
ICMP: echo response sent, source 10.0.0.2, dst 10.0.0.1
ICMP: echo response sent, source 10.0.0.2, dst 10.0.0.1
In the above example, you can see that I only enabled debugging for ICMP events (such as pings). At the output you can see that R1 responded with two IP response packets to the unit with the IP address 10.0.0.1.
To disable ICMP event debugging, type the command with the no keyword:
R1 # no debug ip ipmp
ICMP packet debugging is disabled
To troubleshoot only RIP messages, run the following command:
R1 # debug ip rip
Troubleshooting the RIP protocol is enabled
R1 #
R1 # RIP: Update version 2 from 10.0.0.1 to GigabitEthernet0 / 0 received
172.16.0.0/16 over 0.0.0.0 in 2 jumps
192.168.5.0/24 over 0.0.0.0 in 1 jump
RIP: Version 2 update from 10.0.0.1 to GigabitEthernet0 / 0
172.16.0.0/16 over 0.0.0.0 in 16 jumps
192.168.5.0/24 over 0.0.0.0 in 16 jumps
You can enable debugging of all operations on your device by issuing the debug all command (do not use the command on production units, as it may result in significant output and crash the device!)
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| Debug command |